US8283387B2 - Process for the conversion of synthesis gas to oxygenates - Google Patents

Process for the conversion of synthesis gas to oxygenates Download PDF

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US8283387B2
US8283387B2 US12/227,646 US22764607A US8283387B2 US 8283387 B2 US8283387 B2 US 8283387B2 US 22764607 A US22764607 A US 22764607A US 8283387 B2 US8283387 B2 US 8283387B2
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ether
catalyst
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conversion reactor
conversion
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US20100016453A1 (en
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Leslie W. Bolton
Benjamin P. Gracey
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BP Chemicals Ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/15—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively
    • C07C29/151—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases
    • C07C29/1512—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases characterised by reaction conditions
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
    • C07C1/20—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/15—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively
    • C07C29/151—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of oxides of carbon exclusively with hydrogen or hydrogen-containing gases
    • C07C29/1516—Multisteps
    • C07C29/1518—Multisteps one step being the formation of initial mixture of carbon oxides and hydrogen for synthesis

Definitions

  • the present invention relates to an improved process for the conversion of carbon oxide(s) and hydrogen containing feedstocks to oxygen containing hydrocarbon compounds in the presence of a particulate catalyst.
  • the present invention relates to an improved process for the conversion of carbon oxide(s) (CO and CO2) and hydrogen containing feedstocks, e.g. synthesis gas or syngas, to alcohols in the presence of a particulate modified molybdenum sulphide based catalyst, and/or a modified methanol based catalyst and/or a modified Fischer-Tropsch catalyst and/or a precious metal based catalyst, such as rhodium.
  • CO and CO2 carbon oxide(s)
  • hydrogen containing feedstocks e.g. synthesis gas or syngas
  • U.S. Pat. No. 4,122,110 relates to a process for manufacturing alcohols, particularly linear saturated primary alcohols, by reacting carbon monoxide with hydrogen at a pressure between 20 and 250 bars and a temperature between 150° C. and 400° C., in the presence of a catalyst, characterized in that the catalyst contains at least 4 essential components: (a) copper (b) cobalt (c) at least one element M selected from chromium, iron, vanadium and manganese, and (d) at least one alkali metal.
  • U.S. Pat. No. 4,831,060 relates to the production of mixed alcohols from carbon monoxide and hydrogen gases using a catalyst, with optionally a co-catalyst, wherein the catalyst metals are molybdenum, tungsten or rhenium, and the co-catalyst metals are cobalt, nickel or iron.
  • the catalyst is promoted with a Fischer-Tropsch promoter like an alkali or alkaline earth series metal or a smaller amount of thorium and is further treated by sulfiding.
  • the composition of the mixed alcohols fraction can be selected by selecting the extent of intimate contact among the catalytic components.
  • Journal of Catalysis 114, 90-99 (1988) discloses a mechanism of ethanol formation from synthesis gas over CuO/ZnO/Al2O3.
  • the formation of ethanol from CO and H2 over a CuO/ZnO methanol catalyst is studied in a fixed-bed microreactor by measuring the isotopic distribution of the carbon in the product ethanol when C(13) methanol was added to the feed.
  • a particulate catalyst is defined as being either a supported or unsupported heterogeneous catalyst.
  • the present invention relates to an improved process in terms of selectivity and catalyst activity and operating life, for the conversion of carbon oxide(s) and hydrogen containing feedstocks, e.g. synthesis gas or syngas, to alcohols in the presence of a particulate catalyst;
  • the said particulate catalyst may comprise any one or more of the following: a modified molybdenum sulphide based catalyst; and/or a modified methanol based catalyst; and/or a modified Fischer-Tropsch catalyst; and/or a precious metal based catalyst, such as rhodium.
  • the present invention thus provides a process for the conversion of carbon oxide(s) and hydrogen containing feedstocks to oxygen containing hydrocarbon compounds in the presence of a particulate catalyst, comprising the step of reacting carbon oxide(s) and hydrogen in the presence of a particulate catalyst in a conversion reactor to form products comprising oxygen containing hydrocarbon compounds; characterised in that ether(s) are added and reacted inside the conversion reactor.
  • the present invention provides a process for the conversion of carbon oxide(s) and hydrogen containing feedstocks, e.g. synthesis gas or syngas, to alcohols in the presence of a particulate modified molybdenum sulphide based catalyst and/or a modified methanol based catalyst and/or a modified Fischer-Tropsch catalyst and/or a precious metal based catalyst (e.g. rhodium), comprising the step of reacting carbon monoxide and hydrogen in the presence of said catalyst in a conversion reactor to form alcohols characterised in that an ether is added and reacted inside the conversion reactor.
  • feedstocks e.g. synthesis gas or syngas
  • the present invention provides a process for the conversion of hydrocarbon to alcohols comprising the steps of:
  • producing oxygen containing hydrocarbon compounds from a mixture of carbon oxide(s) and hydrogen means that the oxygen containing hydrocarbons (oxygenates) represent at least 10% by weight, preferably at least 20% by weight, preferably at least 40% by weight, preferably at least 70% by weight and most preferably at least 90% by weight of the total liquid (under STP conditions) products exiting the conversion reactor.
  • the oxygen containing hydrocarbon compounds are alcohols and other organic oxygenates, such as ethers.
  • the alcohols comprise mainly methanol, ethanol, propanols (predominately n-propanol with low amounts of isopropanol) and butanols (predominately n-butanol and isobutanol); said methanol, ethanol, propanols and butanols preferably represent together at least 5% by weight, more preferably at least 10% by weight and most preferably at least 20% by weight of the total liquid (under STP conditions) products exiting the conversion reactor.
  • the ethers may represent all together at least 1% by weight, more preferably at least 2% by weight of the total liquid (under STP conditions) products exiting the conversion reactor.
  • water and carbon dioxide are also produced in the conversion reactor, and the said water, alcohols and ethers preferably represent together at least 50, preferably at least 80% by weight of the total liquid (under STP conditions) products exiting the conversion reactor.
  • the ether(s) which are added into the conversion reactor come directly from the organic oxygenates obtained from the conversion reactor as by-products. Said ether(s) are thus preferably separated from the alcohol(s) produced in the conversion reactor and then recycled back into the said conversion reactor.
  • the ether which is added to the conversion reactor is a methyl, ethyl, propyl and/or butyl ether, preferably a mixture of at least two of these ethers.
  • the ether which is added to the conversion reactor is selected from ethanol and propanol derived ether(s) such as diethyl ether, n-propyl ether, ethyl n-propyl ether, ethyl isopropyl ether, n-propyl isopropyl ether and iso-propyl ether, or even more preferably a mixture of at least two of these said ethers.
  • the particulate catalyst used in the conversion reactor is preferably a modified molybdenum sulphide based catalyst and/or a modified methanol based catalyst and/or a modified Fischer-Tropsch catalyst and/or a precious metal based catalyst (e.g. rhodium).
  • Molybdenum sulphide based catalysts are preferred; these can be modified by a promoter.
  • Promoter(s) can be added as salts during the catalyst preparation, and are preferably potassium ions (e.g. derived from a salt of potassium, such as potassium carbonate or acetate).
  • the preferred loadings of potassium ions per molybdenum is comprised between 0.7 and 1.5, most preferably between 1.0 and 1.4.
  • the preferred catalyst is a molybdenum sulphide based catalysts containing cobalt, the cobalt to molybdenum molar ratio being preferably comprised between 0.5 and 3.0, more preferably between 0.5 and 1.0 and most preferably between 0.5 and 0.9.
  • the ether(s) added to the conversion reactor do not come from the direct recycling of the organic oxygenate compounds produced in the said conversion reactor.
  • the ether(s) come from an indirect route, e.g. from the separation from the olefins obtained during a subsequent step of further chemical processing (i.e. converting the alcohols into corresponding olefins), or from a syngas to dimethyl ether process or from an etherification of methanol.
  • the catalyst used in the conversion reactor can be selected to not produce any ether compound.
  • the ether compound added into the conversion reactor comes from the direct recycling of the organic oxygenate compounds produced in the said conversion reactor.
  • the catalyst used in the conversion reactor can be selected to produce any ether compound in addition to alcohols.
  • hydrocarbon-containing feed stream that can be converted into a feedstock comprising carbon monoxide and hydrogen, most preferably a synthesis gas (or “syngas”), is useful in the processes of the present invention.
  • the hydrocarbon feedstock used according to the present invention is preferably a carbonaceous material, for example biomass, plastic, naphtha, refinery bottoms, smelter off gas, crude syngas (from underground coal gasification or biomass gasification), LPG, gas oil, vacuum residuals, shale oils, asphalts, various types of fuel oils, municipal waste, hydrocarbon containing process recycle streams and coal and/or natural gas; with coal and natural gas being the preferred sources and natural gas being the most preferable source.
  • methane is used as the hydrocarbon feedstock, to be converted into carbon oxides(s) and H2 (e.g. synthesis gas).
  • H2 e.g. synthesis gas
  • synthesis gas Processes for producing mixtures of carbon oxide(s) and hydrogen (commonly known as synthesis gas) are well known. Each method has its advantages and disadvantages and the choice of using a particular reforming process over another is governed by economic and available feed stream considerations, as well as by the desire to obtain the optimum (H2 ⁇ CO2):CO+CO2) molar ratio in the resulting synthesis gas, that is suitable for further chemical processing.
  • the synthesis gas may be prepared using any of the processes known in the art including partial oxidation of hydrocarbons, steam reforming, gas heated reforming, microchannel reforming (as described in, for example, U.S. Pat. No. 6,284,217 which is herein incorporated by reference), plasma reforming, autothermal reforming and any combination thereof.
  • the synthesis gas may be obtained by catalytic partial oxidation of hydrocarbons in a microstructured reactor as exemplified in “IMRET 3: Proceedings of the Third International Conference on Microreaction Technology”, Editor W Ehrfeld, Springer Verlag, 1999, pages 187-196.
  • the synthesis gas may be obtained by short contact time catalytic partial oxidation of hydrocarbonaceous feedstocks as described in EP 0303438.
  • the synthesis gas is obtained via a “Compact Reformer” process as described in “Hydrocarbon Engineering”, 2000, 5, (5), 67-69; “Hydrocarbon Processing”, 79/9, 34 (September 2000); “Today's Refinery”, 15/8, 9 (March 2000); WO 99/02254; and WO 200023689.
  • Feedstocks comprising carbon monoxide and hydrogen may undergo purification prior to being fed to any reaction zones.
  • Synthesis gas purification may be carried out by processes known in the art. See, for example, Weissermel, K. and Arpe H.-J., Industrial Organic Chemistry, Second, Revised and Extended Edition, 1993, pp. 19-21.
  • the ratio of hydrogen to carbon monoxide in the reaction zone is preferably in the range of 20:1 to 0.1:1 by volume, more preferably in the range of 5:1 to 0.2:1, most preferably in the range of 1.5:1 to 0.5:1, e.g. 1:1. It has been found that the alcohol synthesis catalysts can also catalyse the water gas shift reaction. A consequence of this is that hydrogen and carbon dioxide are interconvertible with carbon monoxide and water. For high partial pressures of carbon dioxide (at or above the water gas shift equilibrium), carbon dioxide can act as a carbon monoxide source and a hydrogen sink and this can effect the apparent preferred syngas ratio
  • reaction conditions for the conversion reactor embodiments described hereinafter form preferred embodiments for the present invention
  • reaction conditions outside of these stated ranges are not excluded and in practice the effective reaction conditions may be any that are sufficient to produce mainly oxygen containing hydrocarbon compounds.
  • the exact reaction conditions will be governed by the best compromise between achieving high catalyst selectivity, activity, lifetime and ease of operability, whilst maintaining: the intrinsic reactivity and the stability of the starting materials in question, as well as the desired reaction product to the reaction conditions.
  • feedstock comprising the desired molar ratio of (H2 ⁇ CO2):CO+CO2) is fed to a conversion reactor at a controlled rate and the reaction is carried out in a reaction zone under controlled conditions of temperature and pressure in the presence of a catalyst to convert the feedstock into oxygen containing hydrocarbons.
  • the temperature in the reaction zone is selected from the range of from about 150° C. to about 400° C., preferably a temperature in the range of from about 250° C. to about 350° C. and most preferably in between 280 and 320° C.
  • the pressure in the conversion reaction zone may be selected from the range of from about 20 to 200 bar, preferably a pressure in the range of from about 80 to 150 bar and most preferably at between 80 and 120 bar.
  • the hydrogen and carbon monoxide partial pressures should be sufficient to enable the production of oxygenates.
  • the hydrogen and carbon monoxide may be fed separately to the conversion reactor or, preferably in combination, e.g. as synthesis gas.
  • GHSV gas hourly space velocity which is the rate of gas flow over the catalyst. It is determined by dividing the volume of gas (at 25° C. and 1 atmosphere) which passes over the catalyst in one hour by the volume of the catalyst.
  • the optimum gas hourly space velocity (GHSV) of the feedstock (liters of feedstock/hr/liter of catalyst) passing through the reaction zone can vary significantly, depending upon a variety of factors such as, for example, reaction conditions, composition of the feedstock and quantity and type of catalyst being used.
  • the GHSV can be maintained at any rate in the range of from about 1 to about 30,000 hr ⁇ 1 or more, preferably will be maintained at a rate of between about 500 and 20,000 hr ⁇ 1, and most preferably will be maintained at a rate of between 1,000 and 10,000 hr ⁇ 1.
  • the conversion to oxygen containing hydrocarbons (oxygenates) reaction can be carried out in a conversion reactor by passing the mixture of hydrogen and carbon monoxide over the conversion catalyst as a vapor phase reaction or as a liquid phase reaction, e.g. slurry reaction or trickle bed fluidized bed reactor.
  • the term conversion reactor as used in the present invention pertains to any appropriate reactor, e.g. a tubular reactor using a fixed bed of the catalyst.
  • the reactants may be fed upwards or downwards to the catalyst, or a combination of both, to a fixed bed located in a tubular reactor.
  • the reaction may be effected in a dynamic bed of the catalyst. In such a reaction, the bed of catalyst is moving such as in the case of a fluid bed of the catalyst.
  • the conversion reactor may preferably be chosen amongst tubular, multitubular, slurry, moving bed, fluidised bed, radial bed, multibed or reactive distillation reactor.
  • a fixed bed reactor is used, preferably a radial bed(s) or a multitubular vapour phase reactor or a combination thereof is used.
  • the conversion reactor comprises a series of adiabatic fixed bed reactors operated either in a longitudinal and/or radial flow mode.
  • a potassium promoted cobalt molybdenum sulphide catalyst was prepared according to example “Comparison C” given in U.S. Pat. No. 4,831,060, except for the sulphidation procedure which was performed as indicated below.
  • the catalyst (14.56 g; 10 ml) was loaded into a tubular down-flow reactor (15 mm internal diameter).
  • Gas feeds to the reactor were set to the target composition by Mass Flow Controllers and the gases were premixed before entry to the top of the reactor. Liquids were introduced to the reactor via a HPLC pump set at the target flow rate. The gas and liquid was mixed and vaporised in the pre-heat section in the reactor.
  • the flow rates in the reactor are given as GHSV which is defined as the volume flow of reactant gas at STP per volume of catalyst per hour.
  • Peed changed to 100% nitrogen at a GHSV of 2000 hr ⁇ 1 for purging.
  • the catalyst was brought onto stream by changing gas feed to syngas (CO:H2 ratio of 1) and a 50 ppm stream of H2S at a total GHSV of 2000 h ⁇ 1 .
  • the pressure was increased to 90 Barg and then the temperature was increased (at 1.0 deg C./min) to 310 deg C.
  • the reaction products were analysed by an on-line Gas Chromatogram (CP9001-80-100 Mesh Carbosieve SII and 0.25 micron Innowax columns).
  • the reaction was allowed to run for 235 hours on stream under the above conditions. After which point a 2.5 mol % flow of methanol was fed to the reactor. At 287 hours on stream the methanol feed liquid was changed to a methanol/diethylether mixture (90:10% w/w) and the total liquid pump rate increased such that the methanol flow rate to the reactor remained constant. The additional diethylether feed introduced to the reactor was equivalent to 0.12 mol % of the total feed rate. Product rate data from each different feed period of was averaged from 20 hours after the change in feed (to allow for the feed to stabilise) to the end of each period.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
US12/227,646 2006-06-01 2007-05-25 Process for the conversion of synthesis gas to oxygenates Active 2029-05-23 US8283387B2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP06252833A EP1862443A1 (de) 2006-06-01 2006-06-01 Verfahren zur Umsetzung von Syngas zum Oxygenaten
EP06252833 2006-06-01
EP06252833.6 2006-06-01
PCT/GB2007/001980 WO2007138303A1 (en) 2006-06-01 2007-05-25 Process for the conversion of synthesis gas to oxygenates

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US8283387B2 true US8283387B2 (en) 2012-10-09

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US (1) US8283387B2 (de)
EP (2) EP1862443A1 (de)
CN (1) CN101460438B (de)
ES (1) ES2708841T3 (de)
WO (1) WO2007138303A1 (de)

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Publication number Priority date Publication date Assignee Title
EP2287145A1 (de) 2009-08-12 2011-02-23 BP p.l.c. Verfahren zur Reinigung von Ethylen
WO2013165596A1 (en) 2012-05-03 2013-11-07 Eco Power Solutions (Usa) Corp. Multi-pollution abatement device and method
US20140275634A1 (en) * 2013-03-15 2014-09-18 Gas Technologies Llc Ether Blends Via Reactive Distillation
CN106748647A (zh) * 2016-11-23 2017-05-31 亚洲硅业（青海）有限公司 一种二氧化碳低温等离子氢化法甲醇制备工艺

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4011275A (en) 1974-08-23 1977-03-08 Mobil Oil Corporation Conversion of modified synthesis gas to oxygenated organic chemicals
US4831060A (en) 1984-07-30 1989-05-16 The Dow Chemical Company Mixed alcohols production from syngas
US20070155999A1 (en) * 2005-12-30 2007-07-05 Pujado Peter R Olefin production via oxygenate conversion
US20100069515A1 (en) * 2006-04-13 2010-03-18 Tirtowidjojo Max M Mixed alcohol synthesis with enhanced carbon value use

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4011275A (en) 1974-08-23 1977-03-08 Mobil Oil Corporation Conversion of modified synthesis gas to oxygenated organic chemicals
US4831060A (en) 1984-07-30 1989-05-16 The Dow Chemical Company Mixed alcohols production from syngas
US20070155999A1 (en) * 2005-12-30 2007-07-05 Pujado Peter R Olefin production via oxygenate conversion
US20100069515A1 (en) * 2006-04-13 2010-03-18 Tirtowidjojo Max M Mixed alcohol synthesis with enhanced carbon value use

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
International Search Report for PCT/GB2007/001980, mailed Oct. 2, 2007.
Written Opinion of the International Searching Authority for PCT/GB2007/001980, mailed Oct. 2, 2007.

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Publication number Publication date
EP2021310B1 (de) 2018-12-26
EP1862443A1 (de) 2007-12-05
WO2007138303A1 (en) 2007-12-06
US20100016453A1 (en) 2010-01-21
CN101460438B (zh) 2013-01-23
CN101460438A (zh) 2009-06-17
EP2021310A1 (de) 2009-02-11
ES2708841T3 (es) 2019-04-11

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